<!doctype html>
<html lang="zh-CN">
  <head>
    <!-- 必须的 meta 标签 -->
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">

    <!-- Bootstrap 的 CSS 文件 -->
    <!--<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.0.1/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-+0n0xVW2eSR5OomGNYDnhzAbDsOXxcvSN1TPprVMTNDbiYZCxYbOOl7+AMvyTG2x" crossorigin="anonymous">-->
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	  <link rel="stylesheet" href="bootstrap.css">

    <title>Hello, world!</title>
  </head>
  <body>

    <h1>Hello, world!</h1>
  <botton class="btn btn-primary">按钮</botton>

  </body>
</html>